In an opinion Thursday, Judge Engelmayer dismissed claims by plaintiffs who alleged that they were defrauded into buying Diet Pepsi because they thought that the word “Diet” implied it would help with weight loss.  He found that, in context, the plaintiffs’ alleged inference was not a reasonable one, since the term “Diet” refers to the beverage’s attributes as compared to regular Pepsi:

“Diet” immediately precedes “Pepsi,” and thereby connotes a relative health claim—that Diet Pepsi assists in weight management relative to regular Pepsi. While neither the [complaint] nor plaintiffs’ brief in opposition so much as mentions regular Pepsi, reading “Diet Pepsi” without reference to Pepsi deprives the term “Diet” of its essential referent.  The [complaint] does not dispute that Diet Pepsi assists in weight management relative to regular Pepsi. On this basis alone, plaintiffs cannot maintain a claim that reasonable consumers have been deceived by the term “Diet Pepsi.”

Second, even if the word “diet” may sometimes identify weight-loss products (as in “diet pills” or other products available in a pharmaceutical aisle), in the context of soft drinks, the term unambiguously signals reduced calorie content relative to the non-diet version of the drink in question.  Dictionary definitions specifically defining “diet” in the context of soft drinks confirms this.